Skin packaging

Hot film drapes over product and seals to backing 

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Skin-care products Skin effect Skin flotation Skin infections Skin packaging Skin-So-Soft Skin stains Skiving... 

Very high melt strength is also observed in situations where the molten polymer contacts a sharp object. Skin packaging trials have successfliUy packaged objects such as arrowheads and fishhooks in ionomer films. 

For skin packaging, ionomer films provide outstanding protection, especially for sharp objects. Films can be drawn down tightly around regular shapes without penetration. Characteristics of heat seals can be adjusted so that convenient peelable seals are obtained (31—35). 

Current usage is almost entirely associated with the good adhesion to aluminium. Specific applications include the bonding of aluminium foil to plastics films, as the adhesive layer between aluminium foil and polyethylene in multilayer extrusion-laminated non-lead toothpaste tubes and in coated aluminium foil pouches. Grades have more recently become available for manufacture by blown film processes designed for use in skin packaging applications. Such materials are said to comply with FDA regulations. 

Contour packaging is also called skin packaging. It is package in which thin plastic film or sheet is formed over a product and usually simultaneously sealed to a paperboard or plastic backing. The product serves as a mold. 

An alternative packaging is the combination of food-packaging materials with antimicrobial substances to control microbial surface contamination of foods. For both migrating and nonmigrating antimicrobial materials, intensive contact between the food product and packaging material is required and therefore potential food applications include especially vacuum or skin-packaged products (Vermeiren and others 2002). 

Mitsuda, H., Kawai, F., Kuga, M. and Yamamoto, A. (1973) Mechanisms of carbon dioxide gas adsorption by grains and its application to skin packaging. Journal of Nutrition Science 19, 71-83. 

Skin packaging employs material properties which are similar to stretch wrapping in that the film employed may stretch in the process. However, heat and vacuum are usually employed, hence stretch may also approach an orientation operation. In terms of material, Surlyn ionomer and Saran may be used as well as the more conventional materials. 

Prolonged liberation of immobilized Cl controlled by evaporation and diffusion governs the protective characteristics of the films. Pol3uner films with contact Cl have gained limited application in mainly skin packaging of metal ware [104]. Their anticorrosion properties depend much on the S3meresis intensity of the liquid Cl during which the inhibitor is transported from the pol uner matrix onto the film surface (the physical-chemical bases of this phenomenon have been considered in Sect. 1.4). 

Skin packaging is a combination of a pol3mier film sleeve with a bottom liner (cardboard or sheet polymer). The article is placed on the card liner and is wrapped into the inhibited shrinkage sleeve (Fig. 2.55a). The film ends are fixed on the card, which can also be made of an inhibited material. During heating the film shrinks skin tight around the article. Skin packaging is used for small-size machine parts, spares, tools etc. 

Fig. 2.56. A skin packaging machine using inhibited polymer films (1) base, (2) vacuum chuck, (3) pallet, (4) heater, (5) substrate film, (6) packed articles, (7) and (8) frames for film fastening, (9) film feeding unit, (10) film, (11) needle roller, (12) Cl vessel, (13) Cl applicator castor...

The skin packaging method is advantageous for simultaneous packing of products of different shape and size, it is distinguished by high production standards, rather high efficiency and package quality. 

Fig. 2.57. Hardware packed into inhibited PE film by a skin packaging method...

Films of EAA are also used in flexible packaging of meat, cheese, snack foods, and medical products in skin packaging and in adhesive lamination. Extrusion coating applications include condiment and food packages, coated paperboard, aseptic cartons, composite cans, and toothpaste tubes. FDA regulations permit use of up to 25% acrylic acid for copolymers of ethylene in direct food contact. 

Figure 10.12 Skin packaging (reprinted with permission from [1])...

What are the major advantages and disadvantages of skin packaging compared to blister packaging ... 

Film Applications Packaging films and sealants meat, seafood, poultry, cheese, snack, skin packaging/stretch pack, personal and health care, and liquid packaging. 

Uses Adhesive/sealant resin for use in blown and cast film extrusion applies, incl. meat/poultry/seafood/cheese pkg., cereal liners, medical/ pharmaceutical pkg., powd./granularfood and non-food pouches, carded display/skin packaging films edible oil, motor oil, other li prod, pouches, snack structures coextrusions with nylon or in other film structures as heat seal or tie layer Features High clarity grade Regulatory FDA 21 CFR 177.1330 compliant Properties Melt flow 1.5 dg/min f.p. 78 C m.p. 103 C Vicat soften, pt. 81 C ultimate tens. str. 33.1 MPa (MD) ultimate elong. 450% (MD) Spencer impact str. 29 J/mm Dart drop str. 7.9 g/pm Elmendorf tear str. 46.3 mN/pm 9% methacrylic acid... 

Skin packaging n. A variation of the thermoforming process in which the article to be packaged serves as the mold. The article is usually placed on a printed card prepared with an adhesive coating or mecharucal surface treatment to seal the plastic film to the card. 

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